1. Technical Field
This invention relates to flexible tubing and, more particularly, to thermo-insulated flexible tubing for insulating a flow of water in extreme weather conditions.
2. Prior Art
People living in areas where ambient temperatures have a tendency reach either cold or warm extremes at some point during the year, are quite familiar with the problems associated with tubes and pipes that carry water. In areas where extreme cold temperatures are encountered, one must frequently deal with frozen water in the pipe lines and tubing of structures. This is inconvenient since access to water is limited and the chemical properties of water cause the water to expand upon freezing, which can lead to burst pipes and tubes. Obviously, it can become quite expensive to annually replace broken pipes and tubes.
On the other end of the spectrum, there are the problems associated with extremely high ambient temperatures. Cold water carried in tubes and pipes in these areas have a tendency to become over heated and not suitable for use. The metal tubes and pipes used also have a tendency to expand in extreme heat, thus diminishing the effective water flow rate. This can make showers and watering one's garden quite an inconvenient experience, since a greater amount of time is needed to dispense the needed amount of water. As such, insulated tubing and pipes have been introduced to the prior art.
One example discloses a thermally insulated tube construction which includes a metal tube, and a metal ribbon coaxially enveloping the tube and being spaced therefrom by synthetic foam. In particular, a foam on the basis of polyisocyanurate is used which has been made flame resistant. Also, the metal ribbon is coated with a flame-resistant copolymer. The foil or metal ribbon formed into an outer tube serves as a kind of mold. Upon forming this tube, the edges of the foil are folded up, resulting in a radially outwardly extending and cemented tab which is subsequently folded down onto the surface of this tube.
This known tube is quite expensive to make, and the foil edges and tab are highly visible. Moreover, the tube just barely meets flame-resistant standards as and then only in the beginning. Sooner or later, the flame-resistant additives diffuse more or less rapidly out of the foam, so that the actually provided protection lasts only temporarily. Moreover, the known flame-retarding additives which are included in the foam can also frequently act as a softener, thereby interfering with the spacing and support function of the insulation. The insulation foam also becomes thermally instable in some cases.
Accordingly, a need remains for a thermo-insulated flexible tubing in order to overcome the above-noted shortcomings. The present invention satisfies such a need by providing thermo-insulated tubing that is efficient in its designed function, inexpensive to produce and easy to install. The air gap between the two layers provides a good level of thermal insulation, thereby making it resistant to freezing and helps to minimize heat loss through the water lines. Such thermo-insulated tubing further eliminates the need to apply foam insulation about the tube, thus saving a considerable amount of time and energy.